Thumim



C. THUMIM SAFETY PIN MECHANISM FOR GUILLOTINE TYPE PAPER CUTTERS Filed Aug. 9, 1957 2 Sheets-Sheet 1 INVENTOR. 6%64 W/dM/M Oct. 4, 1960 c;. THUMIM SAFETY PIN MECHANISM FOR GUILLOTINE TYPE PAPER CUTTERS Filed Aug. 9, 1957 2 Sheets-Sheet 2 J m E r M a m W w Carl Thumim, Westbury, N.Y., assiguor to E. P. Lawson Co., Inc., New York, N.Y., a corporation of New York Filed Aug. 9, 1957, Ser. No. 677,350

2 Claims. (Cl. 188-68) This invention relates to guillotine type paper cutters and more particularly to a safety pin mechanism to prevent recycling thereof.

Safety pins are known in conjunction with paper cutters and are generally so arranged as to move into a position to block a gear which actuates the knife after a cutting cycle has been completed so that the knife will not accidentally recycle. One arrangement for effecting such a safety feature is shown in Patent 2,570,873 assigned to the present assignee.

The present invention relates particularly to cutting machines having a knife driving mechanism acting through an electric clutch as shown in my copending patent applications Serial No. 626,214, filed Dec. 4, 1956, and Serial No. 660,795, filed May 22, 1957.

Among the objects of the present invention are to provide a system wherein the knife may be manually inched without, however, arriving at a point at which the safety pin effects blocking off the knife moving mechanism. Such blocking causes binding of the mechanism which requires considerable force to loosen. Another object of the invention is to provide a safety pin normally solenoid actuated into unblocking position and spring actuated into blocking position but which, in the event of failure of the spring actuation, would be mechanically moved into blocking position by a positive force.

Other objects and features of the invention will be apparent from the description which follows in conjunction with the appended drawing in which:

Figure 1 is a section through a portion of the machine showing one of the gears that drives a crank which actuates a pull bar at one end of the knife, together with associated mechanism operative in conjunction with the safety pin.

Figure 2 is a fragmentary detail in section of a portion of the mechanism operative with the safety pin for the purpose of preventing blocking of the gear by the safety pm.

Figure 3 is a fragmentary drawing in section showing the safety pin and its associated solenoid mechanism and spring for actuation thereof.

Figure 4 is a fragmentary drawing showing a portion of the safety pin mechanism as it relates to the control circuit for the machine.

Figure 5 is a front view showing fragrnentarily the arrangement of the safety pin mechanical actuator which serves to insure motion of the pin into blocking position mechanically in the event of failure of the return spring.

Fig. 6 is a view of the cammed construction looking in the direction 66 of Fig. 5.

Fig. 7 is an enlarged view of certain components shown in Figs. 1 and 2.

It will be understood that the present case relates directly to the copending applications identified above and that any material not shown herein has been omitted in order to avoid duplication; reference should be made to Fatented Get. 4, 1960 the copending applications for a fuller understanding, where necessary, of the disclosure herein made.

Referring now to Figures 1 and 2 of the drawing, a gear 18 on shaft 90 is shown which gear will be understood to be a part of the mechanism which drives a pair of crank shafts which in turn rotate respective crank pins that operate pull bars for actuating the knife all as shown in copending application Serial No. 661,534, filed May 24, 1957. The relative position of the safety pin 22 is shown with reference to the gear 18. Gear 18 carries a pivot pin 25 on which is pivotally carried a dog 28 biased in a counterclockwise direction by means of a spring 32 slidably carried on a pin 35 which is pivotally supported on the pin 23. The spring 32 serves to maintain an upward pressure on dog 28 thereby biasing it to a position where the abutment shoulder 41 of the dog 28 strikes an inner peripheral surface of a lug 44 integral with the gear 18. It will be seen that the lug 44 has an abutment shoulder 47 which can be engaged by the pin 22 When the pin protrudes into the gear, thus to prevent further rotation of the gear.

When it is desired to inch the machinewithout bringing about engagement of pin 22 with shoulder 47, i.e., to avoid binding, the pin 22 initially strikes the sloping surface 50 of the dog 28 and is kept from going all the Way into engagement position with shoulder 47. Under abnormal overtravel operation with the pin 22 all the way in, the dog 28 will be pushed all the way clockwise and the safety pin 22 will clear the dogand strike shoulder 47 to positively block rotation of gear 18.

The arrangement described above avoids binding during inching and thus eliminates the necessity of having to turn the flywheel (not shown) backwards to relieve binding in machines which do not have the feature described.

Referring now to Figure 3, the safety pin 22 is shown supported in a frame panel 53 and further supported in a stationary lug 56 which will be understood to be inside the gear housing. Associated with the safety pin is a solenoid 60 carried by the machine frame, as shown, and which serves to retract the pin toward the right, when energized, against the bias of a spring 63, in a manner hitherto known. The energization of the solenoid 60 takes place in accordance with operation of an electrical control circuit as shown in copending application Serial No. 660,795.

Referring now to Figure 4, it will be noted that pin 22 carries a pin 66 which rockably engages a lever 70. Lever 70 is pivotally supported by a pin 73 fixed in a block 76 fastened to the machine frame. Thus, it will be apparent that as the pin '22 moves back and forth it will cause rocking of the lever 70. It will be understood that proper slots are provided between the lever and the safety pin to take care of the arcuate versus lineal motions of these members. The lever 70 carries a roller 80 which can coact with a double cammed surface 83 of a crank arm 86 which rotates shaft and operates a knife pull bar (not shown) as disclosed in copending application Serial No. 661,534. The cam surface is so shaped as to gradually engage the roller 80 as the arm 86 rotates.

The purpose of providing engagement between crank arm 86 and roller 80 is to effect positive motion of pin 22 into blocking position should spring 63 fail to return the pin due to breakage, dirt, etc. It will be appreciated that the cam surface will cause rocking of the lever 70 and thus move the pin into blocking position.

The lever 70 has another function in that it carries an adjustable screw 84 engageable with the button of a microswitch 87 which switch will be understood to be fixed to the machine frame. Screw 84 actuates switch 87 when pin 22 is withdrawn that is, in unblocking position. Thus, actuation of the switch effects through the control circuit vof the copending application Serial No. 660,795 energization of the electromagnetic clutch through which the knife is powered.

Having thus described my invention, I am aware that various changes may be made, Without departing from the spirit thereof, and accordingly I do not seek to be limited to the precise illustration herein given except asset forth in the appended claims.

I claim:

1'. In a machine of the class described, said machine having a name, a drive gear having a shoulder disposed for abutment With a safety pin; a safety pin reciprocally mounted on said frame to move into or out of abutting position with respect to said shoulder; and brake means carried by said gear initially engageable by said safety pin to slow rotation of said gear prior to abutment of said pin with said shoulder, when said gear is rotating at normal speed, and to stop rotation of said gear prior to abutment of said pin with said shoulder when said gear is rotating at less than normals'peed, said brake means corn-prising a spring loaded member, carried by said gear and disposed for engagement with said safety pin, said spring loaded member being rockably carried by said gear and having a cam surface engageable by said safety pin to rock said member against the bias of said spring loading. a,

2. In a machine of the class described, a machine frame, a rotative drive gear having a shoulder disposed for abutment with a safety pin; a safety pin reciprocally mounted on said frame for movement into and out of abutting position with respect to said shoulder, a crank arm connected for rotationi with' said drive gear; and driven thereby, and means intermediate said crank arm and said safety pin for effecting motion of said pin into a positi'ohf abutment with -sai shoulder at a predeterrn'ined point iii the rotati've cycle of said ge r, said means comprising an element rotative said crank arm and follower means connected to said pin and engageable by said element to effect said motion of said pin, said element comprising a cam; said follower means comprising a lever pivotally connected to said pin; and means carried by said lever engageable by said'cam to actuate said lever for effecting said motion of said pin.

Referencesited in the file of this patent UNITED-STATES PATENTS 

